Marty,
I have a bunch of MTH Bump and Go's. They work well for almost any application, and have rollers as you have mentioned.
I bought one Lionel trolley. It had sliding "shoes" and I had a tough time keeping it running. On EZ streets with a shallow center rail, I think it would not work as well.
Atlas Industrial Rail trolleys also have rollers. They're a bit longer, and are both Bump and Go AND have an E-unit. Nice design.
Ed